Advertisement

Formation mechanism of gradient-distributed particles and their effects on grain structure in 01420 Al-Li alloy

  • Xin-ming Zhang (张新明)
  • Ling-ying Ye (叶凌英)Email author
  • Ying-wei Liu (刘颖维)
  • Yu-xuan Du (杜予晅)
  • Zhi-hui Luo (罗智辉)
Article

Abstract

Fine-grained 01420 Al-Li alloy sheets were produced by thermo-mechanical processing based on the mechanism of particle stimulated nucleation of recrystallization. The thermo-mechanically processed sheets were observed to contain layers of different microstructures along the thickness. The precipitate behavior of the second phase particles and their effects on the distribution of dislocations and layered recrystallized grain structure were analyzed by optical microscopy(OM), scanning electron microscopy(SEM), transmission electron microscopy(TEM) and X-ray diffractometry(XRD). The formation mechanism of the gradient particles was discussed. The results show that after aging, a gradient distribution of large particles along the thickness is observed, the particles in the surface layer(SL) are distributed homogeneously, whereas those in the center layer(CL) are mainly distributed parallel to the rolling direction, and the volume fraction of the particles in the SL is higher than that in the CL. Subsequent rolling in the presence of layer-distributed particles results in a corresponding homogeneous distribution of highly strained regions in the SL and a banded distribution of them in CL, which is the main reason for the formation of layered grain structure along the thickness in the sheets.

Key words

01420 Al-Li alloy layered grain structure grain refinement thermo-mechanical processing particle stimulated nucleation(PSN) 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. [1]
    NIEH T G, WADSWORTH J, SHERBY O D. Superplasticity in metals and ceramics[M]. Cambridge: Cambridge University Press, 1997.CrossRefGoogle Scholar
  2. [2]
    HUMPHREYS F J, HATHERLY M. Recrystallization and related annealing phenomena[M]. 2nd ed. Oxford: Pergamon Press, 2004.Google Scholar
  3. [3]
    YE Ling-ying, ZHANG Xin-ming, DU Yu-xuan, LUO Zhi-hui. Particle-stimulated nucleation of recrystallization for grain-size control in 01420 Al-Li alloy[J]. Materials Science Forum (Part 2), 2007, 546/549: 889–892.CrossRefGoogle Scholar
  4. [4]
    TROEGER L P, STARKE J E A. Particle-stimulated nucleation of recrystallization for grain-size control and superplasticity in an Al-Mg-Si-Cu alloy[J]. Materials Science and Engineering A, 2000, A293(1): 19–29.CrossRefGoogle Scholar
  5. [5]
    HUMPHREYS F J. Particle stimulated nucleation of recrystallization at silica particles in Inckle[J]. Scripta Materialia, 2000, 43(7): 591–596.CrossRefGoogle Scholar
  6. [6]
    HUMPHREYS F J. Nucleation in recrystallization[J]. Materials Science Forum (Part 1), 2004, 467/470: 107–116.CrossRefGoogle Scholar
  7. [7]
    DOHERTY R D, HUGHES D A, HUMPHREYS F J, JONAS J J, JUUL JENSEN D, KASSNER M E, KING W E, MCNELLEY T R, MCQUEEN H J, ROLLETT A D. Current issues in recrystallization: A review[J]. Materials Science and Engineering A, 1997, A238(2): 219–274.CrossRefGoogle Scholar
  8. [8]
    DU Yu-xuan. Principles and techniques in preparation of superplastic Al-Li sheets[D]. Changsha: Central South University, 2006. (in Chinese)Google Scholar
  9. [9]
    CHATURVEDI M C, KASHYAP B P, FAN W. Microtextural evolution during superplastic deformation of AA 8090 Al-Li alloy[J]. Materials Science and Technology, 2001, 17(3): 237–248.CrossRefGoogle Scholar
  10. [10]
    FAN W, KASHYAP B P, CHATURVEDI M C. Anisotropy in flow and microstructural evolution during superplastic deformation of a layered-microstructured AA8090 Al-Li alloy[J]. Materials Science and Engineering A, 2003, A349(2): 166–182.CrossRefGoogle Scholar
  11. [11]
    FAN W, KASHYAP B P, CHATURVEDI M C. Effect of composite-like microstructure on superplastic flow and concurrent microstructural evolution in AA8090 Al-Li alloy[J]. Canadian Metallurgical Quarterly, 2003, 42(2): 219–230.CrossRefGoogle Scholar
  12. [12]
    FAN W, KASHYAP B P, CHATURVEDI M C. Effect of layered microstructure and its evolution on superplastic behaviour of AA 8090 Al-Li alloy[J]. Materials Science and Technology, 2001, 17(4): 439–445.CrossRefGoogle Scholar
  13. [13]
    FAN W, KASHYAP B P, CHATURVEDI M C. Effects of strain rate and test temperature on flow behaviour and microstructural evolution in AA8090 Al-Li alloy[J]. Materials Science and Technology, 2001, 17(4): 431–438.CrossRefGoogle Scholar
  14. [14]
    ZHENG Zi-qiao, HUANG Bi-ping. Effect of heat treatments on tensile properties and microstructure of 2195 alloy [J]. Journal of Central South University of Technology, 1998, 5(1): 14–17.CrossRefGoogle Scholar
  15. [15]
    TAN Cheng-yu, ZHENG Zi-qiao, XIA Chang-qing, LIANG Ying. The aging feature of Al-Li-Cu-Mg-Zr alloy containing Sc [J]. Journal of Central South University of Technology, 2000, 7(2): 65–67.CrossRefGoogle Scholar
  16. [16]
    WANG Shu-yun, ZHANG Xiao-bo, CUI Jian-zhong, ZHANG Cai-pei. Comparision on the superplasticity of two Al-Mg alloys[J]. Hot Working Technology, 1997(1): 20–22. (in Chinese)Google Scholar
  17. [17]
    WANG Shu-yun, ZHANG Xiao-bo, CUI Jian-zhong, ZHANG Cai-pei, Studies of superplasticity in an Al-Mg-Li-Zr alloy[J]. Light Metal, 1997(5): 50–52. (in Chinese)Google Scholar
  18. [18]
    ZHANG Xin-ming, YE Ling-ying, DU Yu-xuan, LUO Zhi-hui. Particle stimulated nucleation of recrystallization in 01420 Al-Li alloy[J]. Journal of Central South University, 2007, 38(1): 19–23. (in Chinese)Google Scholar

Copyright information

© Central South University 2008

Authors and Affiliations

  • Xin-ming Zhang (张新明)
    • 1
    • 2
  • Ling-ying Ye (叶凌英)
    • 1
    • 2
    Email author
  • Ying-wei Liu (刘颖维)
    • 1
    • 2
  • Yu-xuan Du (杜予晅)
    • 1
    • 2
  • Zhi-hui Luo (罗智辉)
    • 1
    • 2
  1. 1.Educational Key Laboratory of Non-ferrous Metal Materials Science and EngineeringCentral South UniversityChangshaChina
  2. 2.School of Materials Science and EngineeringCentral South UniversityChangshaChina

Personalised recommendations